This invention relates to trailer hitch locators. More specifically, it refers to an optical sensor system for assisting a backing motor vehicle operator in aligning a hitch ball on the rear of the vehicle to a trailer hitch.
The task of aligning a vehicle ball with a trailer hitch is a difficult and sometimes frustrating one. Many systems have been developed in the prior art in an attempt to make this alignment task easier. Magnetically activated electrical switches were describe in U.S. Pat. No. 5,108,123. Other magnetic coupling devices were described in U.S. Pat. Nos. 5,729,194; 5,861,814 and 6,178,650. A recent development employs an infrared light and sensor mounted on the bumper of the towing vehicle. A reflective device on the trailer hitch returns infrared light impulses back to the sensor which transmits audible signals to the driver. See U.S. Pat. No. 6,259,357. In U.S. Pat. No. 6,480,104, a multiplicity of ultrasonic transducers gauge the location of the towing vehicle to the trailer. The information is transmitted to a control unit which creates a visual display for the operator. While these recently developed systems improve the ability of a driver to align his vehicle with a trailer hitch, they are expensive and the data furnished to the driver is difficult to interpret. A simpler inexpensive system is needed to assist a driver in quickly and easily aligning his vehicle to a trailer hitch.